The present invention relates to the testing of circuits in which an alarm is triggered by a momentary short in a normally-open circuit, or for testing the connections during installation of a normally-closed circuit.
Presently, normally-open alarm systems are tested manually by physically inserting flats, instruments similar to needle-nosed pliers, into the alarm junctions. This testing method has significant drawbacks. First, if the alarm site is remote from the alarm control center, this method requires two operators: one operator at the alarm site to trigger the alarm, and a second operator at the control center to confirm that the alarm is properly triggered and indicated at the control center. Second, the manual insertion of flats to test the alarm system exposes the operator to a safety risk. Other disadvantages also exist as a result of the imprecision of this method: depending on the wiring at the testing site of circuitry for various alarm systems, inserting flats may short out other alarm circuits. Additionally, some alarm circuit blocks used in the communications field have a power source on the same block. If the flats come into contact with the power source, the alarm circuit may be damaged.
A primary drawback of conventional normally-closed alarm systems concerns testing during installation of the system, in order to ensure that the alarm circuitry is properly installed. Presently, installers will set up an alarm system having multiple sites where the alarm can be triggered and connect cables leading from each of these sites to a central control center. Because the alarm cables are bundled together, the installer has no easy way to determine which cable comes from which site. For instance, home alarm systems typically are normally-closed systems that can be triggered by breaking the alarm circuit at various entries to the home. To determine whether the alarm circuitry is properly in place at each site, the installer can test each cable leading to an alarm site at the control center. However, if an open circuit for a particular cable does not properly trigger an alarm at any of the alarm sites, or if the operator is working alone and cannot determine whether an alarm has been triggered at a remote alarm site, the installer will not be able to easily determine at the control center which alarm site is not properly connected.
Thus, there exists a need for a device and a method allowing alarm circuitry to be tested by a single operator, and which permits the operator to test the circuitry without being exposed to safety risks. There also exists a need for a more efficient and effective method for testing whether a normally-closed alarm system has been properly installed.